The Lord (swt) indicates that these Paradises that He has prepared for the believers, along with this tremendous contentment and immense mercy, and this unimaginable bestowal in the hereafter, are eternal. The blessings will never abandon you, nor will you leave them, forever.

(…إِنَّ اللَّهَ عِندَهُ أَجْرٌ عَظِيمٌ) (Indeed, Allah has with Him a great reward.): This immense reward, this recompense, and the enduring bliss, along with the perpetual and everlasting bestowal, are what Allah (swt) has designated for human beings based on their good deeds in the worldly life. It is a reward for their fulfillment of the commands of Allah (swt) and their avoidance of His prohibitions.